Ortho/Pedo Flashcards
(153 cards)
1
Q
The condition known as “twinning” is also called ___ (the technical term)
A
Gemination
2
Q
The loss of tooth L in a 5-year-old patient requires ___ for space management. Why?
A
Band-and-loop
It will prevent the mesial movement of K into the space created by extracting L
It should be replaced with a lingual holding arch as soon as the other lower permanent incisors erupt
3
Q
Space maintainers should not be placed in children ___ years of age or younger
A
3
4
Q
What causes the discontinuity of the occlusal plane when an ankylosed tooth is present?
A
Continued eruption of non-ankylosed teeth and growth of the alveolar process
When teeth are ankylosed, they usually lie below the occlusal plane because the supporting alveolar process does not grow.
Alveolar process growth occurs simultaneously with the eruption of teeth. Ankylosed teeth do not experience alveolar process growth because of their failure to erupt the same way as the other non-ankylosed teeth due to a lack of PDL.
5
Q
___ is the term for a tooth that is traumatized without being displaced and can also increase the mobility of the tooth. ___ confirms the diagnosis.
A
Subluxation
Bleeding from the gingival sulcus
This trauma may require immediate dental treatment of the affected tooth
6
Q
___ occurs when there is an injury within the supporting structures of a traumatized tooth and does not demonstrate bleeding from the sulcus. Loosening and possible displacement among traumatized teeth is NOT observed.
A
Concussion
7
Q
To obtain optimal retention of a stainless steel crown in a primary mandibular molar, the __ surface should have the least amount of reduction.
A
Lingual
The lingual cervical bulge is smaller than the buccal so the lingual reduction must be minimal
8
Q
Fusion results from the union of two ___. It is usually found in ___ teeth.
A
Adjacent tooth buds
Anterior
9
Q
An anomaly in which there is a distortion of only the root of a tooth, which may be in the form of a right angle bend is a ___
A
Flexion
10
Q
What is the difference between a dilaceration and a flexion?
A
Flexion is distortion of the root portion only
Dilaceration is distortion of the root AND crown from their normally linear relationship
11
Q
What is concresence?
A
The union of the root structure of two or more teeth through cementum only
12
Q
What is a dwarfed root and a segmented root?
A
Dwarfed root - normal sized crowns with abnormally short roots
Segmented root - two separated root segments resulting from break in hertwig’s sheath
13
Q
Development of pulp necrosis is most commonly seen in what type of dental trauma?
A
Intrusion. It may sever the nerve and blood vessels that supply the tooth resulting in pulp necrosis. It may also cause replacement resorption of the roots or ankylosis
Concussion, extrusion, luxation, and subluxation are accidents that are less likely to involve the vascular supply of the tooth
14
Q
What is a flexion and how is it caused?
A
A deviation or a bend of less than 90 degrees at the root of tooth that results from trauma during development
15
Q
Dwarfed roots are normally found in ___ teeth, with __ being the most common
A
Anterior
Maxillary central incisors
16
Q
How is a dilaceration formed?
A
Likely resulted from trauma during development
Trauma during tooth development may result in the position of the calcified portion of the tooth being changed so that the remainder of the tooth is formed at an angle.
The curve or bend may occur anywhere along the length of the tooth and depends on the amount of root that is already formed when the injury is sustained.
17
Q
What teeth anomalies are associated with prenatal syphilis (caused by the bacteria:__)? How does it cause the anomaly? What teeth are they likely to affect?
A
Hutchinson’s teeth and mulberry molars
Treponema Pallidum
It disturbs the calcification of the teeth during the mopodifferentiation of ameloblasts
Incisors (maxillary central) and 1st molars are commonly affected because they are the only permanent teeth at this stage of development
18
Q
What is the primary concern of patients with Hutchinson’s teeth and mulberry molars?
A
Esthetics
19
Q
True or false.. prenatal syphillis affects primary teeth
A
False
20
Q
____ is an abnormal bone growth condition where normal bone is replaced with fibrous bone tissue, causing a “ground glass” appearance radiographically. Cortex may be thinned and displaced. The bones of the skull, thigh, shin, ribs, upper arm, and pelvis are most commonly affected. 70% are ___ and involve just one bone.
A
Fibrous dysplasia
Monostotic
21
Q
Fibrous dysplasia occurs 50% more frequently in the __ than the __
A
Mandible
Maxilla
22
Q
Describe the radiographic features of Fibrous Dysplasia
A
Ground glass appearance (radiopaque (usually or radiolucent)
Usually unilocular
Cortex thinned and may be displaced
Displaces anatomical structures and may or may not displace teeth
Poorly defined with no corticated border
Loss of lamina dura
23
Q
___ is a rare genetic disorder characterized by a bony prominence in the lower portion of the face and unerupted permanent teeth. It is also associated with premature deciduous tooth loss due to the sponge-like quality of bone. It is associated with the uneruption of permanent teeth due to displacement by cysts and lesions.
A
Cherubism
24
Q
True or false… in cherubism, the condition often fades as the child grows
A
True
25
What are the ABCDEs of early signs of melanoma?
```
A-Asymmetry
B-Border (irregular)
C- Color (multicolored)
D- Diameter (greater than about 6mm)
E- Evolving
```
26
The most dangerous form of melanoma, ___, can be diagnosed by “EFG”. What does that stand for?
Nodular melanoma
E- Elevated above the skin surface
F- Firm to the touch
G- Growing
27
What happens to the morphology of oral mucosa in an aspirin burn?
Tissue necrosis
The acetylsalicylic acid in aspirin burns the mucosa causing coagulation necrosis
28
____ are congenital multiloculated lymphatic lesions that can arise anywhere but are classically found in the left posterior triangle of the neck in children. They are considered to be the most common form of lymphangioma. They contain large, cyst-like cavities containing lymph, and they decrease in size as they approach the surface of the skin. They are benign but can be disfiguring
Cystic hygromas
29
What are the two types of cystic hygromas?
Macrocystic lymphatic malformations (large cysts)
Microcystic (small cysts
A person can have one type of a cyst or a mixture of both.
30
True or false.. a cementoblastoma indicates the presence of a necrotic pulp
False
31
____ are benign lesions that usually appear in males under the age of 25 and involve the permanent mandibular molars or premolars. They typically appear as a well-defined, marked radiopaque mass, with a radiolucent peripheral line, which overlies and obliterates the tooth tooth.
Cementoblastomas
32
Describe how the sclerotic reaction of condensing osteitis occurs.
The sclerotic reaction results from a strong resistance of the patient and a low degree of virulence of the offending bacteria
33
As enamel ages, it becomes ___, __, and ___.
Thinner
Less translucent
Worn
Younger teeth exhibit thicker, more translucent, and rougher enamel.
Adult teeth appear smoother, shorter, and darker
34
Which Angle’s classification is most likely to occur as an adult when the primary second molar teeth exhibit a distal step?
Class 2
35
Mesial step occlusion usually results either class __ or class __ molar relationships after eruption of permanent teeth.
1
3
36
Children with a flush terminal plane occlusion, will end up in a class __, class __, or __ type of molar relationship
1
2
End to end
37
A 10 year old patient presents to you with a 2.5mm diasterma and a low attached maxillary labial frenum. What is the best option for this patient? Why?
Observe until after eruption of permanent canines
Diastema in between maxillary central incisors normally occur during the mixed dentition stage. Eruption of maxillary canines in children ranging from age 11 to 12 usually will close the diastema between the maxillary central incisors.
38
When is a frenectomy indicated in the case of a midline diastema?
If the maxillary canines had already erupted and were unable to close the diastema due to a lowly attached or fibrous maxillary labial frenum.
39
The aging process causes the facial profile to become less __. How else is the face affected by aging?
Convex
Loss of facial fat, muscle atrophy, and loss of skin elasticity
The buccal fat pad is gradually lost in the cheeks causing the skin to adapt itself to the underlying muscle and bone
During the aging process, metabolism slows down and the production of skin, collagen, and muscle fibers is reduced. The constant pull of gravity also contributes to the sagging of the face.
40
A 9 year old patient presents to your office with a unilateral posterior crossbite with a functional shift. What is the appropriate timing for correction of the crossbite?
Immediately, when the child is approximately 9 years of age.
Unilateral posterior crossbite are best treated immediately after their diagnosis
Treatment is most appropriate for children who are currently in the late deciduous at this age and more space is created to correct the malaignment
41
Cervical pull headgear is an appliance used to correct ___ malocclusions with ___. The neck strap acts to ___. The outer bow connects the facebow assembly with the neck strap. The inner bow is inserted into the tubes found on the ___ bands/brackets.
Class 2
Deep bite
Extra-oral anchorage
Molar
42
Cervical pull headgear inhibits the growth of the ___ and causes the ___ to extrude lessening the ___. The headgear must be worn regularly for ___ per day for optimal results.
Maxilla
Maxillary molars
Deep bite
12 hours
43
The most common reason or improper speech sounds in cleft lip and palate patients is mainly due to...
Inability of the soft palate to close airflow into the nasal area and inability of the tongue to stop airflow from the epiglottis
44
What is the sequence of eruption for primary teeth?
Central incisor, lateral incisor, first molar, canine, second molar
45
Loops and helices are incorporated into arch wire to...
Improve activation range. Activation is created by slightly closing the loops and helices with a pair of pliers.
Archwires need to be activated to achieve the desired results as it becomes loose after moving teeth in the desired direction decreasing the tension on the arch wire.
Closing the loops and helices result in the tightening of arch wire.
46
Due to the long axis of the teeth, the spontaneous closure of the extraction space in the ___ arch is better than the __ arch.
Upper
Lower
47
During the eruption of the permanent 2nd and 3rd molars, what portions of the developing mandible help provide space?
Resorption at the anterior border of the ramus while bone is simultaneously deposited at the posterior border of the ramus. This helps maintain the ramus width while providing extra alveolar bone space for the erupting molars.
48
True or false... condylar hypertrophy cannot cause an anterior open bite
True
49
In order to effectively translate the roots of teeth, orthodontic appliances must be capable of..
Exerting a torque/movement coupling action.
50
Approximately __-__g of force is needed to uniformly load the PDL to create translational movement.
100-150
51
A higher-than-average mandibular plane angle indicates a [horizontal/vertical] growth pattern and an [increased/decreased] lower anterior face height
Vertical
Increased.
52
True or false.. patients with deep overbites and a vertical growth pattern may exhibit steep mandibular plane angles but NOT a long lower anterior face height due to the type of dental occlusion that the patient demonstrates
True
53
Approximately __% of a permanent tooth’s root structure has typically developed right before the tooth first emerges into the oral cavity
66% (2/3rds)
The tooth begins to erupt when the root reaches about 2/3 of its complete form.
54
Vertical growth of the mandible is attributed to growth of the __
Condylar head
55
Primary tooth formation begins ___ -___ weeks in utero. Calcification of primary teeth begins during the ___ trimester.
6-8 weeks
2nd trimester (14th - 19th week)
56
The cusp of carabeli is a feature most commonly found on which Primary tooth? Which permanent tooth? Which cusp is it on?
Maxillary 2nd molar
Maxillary first molar
Lingual to the ML cusp
57
What is adjunctive orthodontics?
Adjunctive orthodontic treatment integrates favorable orthodontic tooth movement into a treatment plan together with other dental procedures (perio, prosth, operative).
This also eliminates unnecessary tooth extractions, tooth preparations, and other periodontal, preprosthetic, or pre-restorative treatment to achieve more optimal outcomes
58
Cervical pull headgear is an appliance used to reduce ___ growth of the maxilla.
Forward
59
Which tooth is most likely to NOT erupt in the arch due to overcrowding?
Canine (because they come in after the incisors and premolars have already erupted)
Tooth crowding carries a genetic predisposition because it is often a matter of tooth size vs arch size discrepancy
60
The permanent molars shift mesially to close which space?
Leeway space - created from the difference of sizes between the primary canine and molars compared to the erupting premolars and permanent canines
61
Which cephalometric measurement value indicates that if the maxilla is protruded or returned?
SNA (sella-nasion-A point)
62
The __ cephalometric value is a useful guide in determining the relation of maxilla to the mandible.
ANB
63
During postnatal growth of the maxilla, an increas in maxillary height and depth of the palate is atributed to growth of the __
Alveolar bone
64
A 6-year-old presents with need of extraction of L and S. The mandibular incisors have not yet erupted. The indicated method of space maintenance for this patient is...
Bilateral band and loops because the mandibular permanent incisors have not yet erupted.
65
___ appliances are cemented on the maxillary permanent first molars and have an acrylic button that rests on the palate to resist forward movement
Nance
66
Which three planes of space are used to classify malocclusion? Describe what each plane defines.
Sagittal - describes AP relationships (class 1, 2, 3)
Transverse - describes right to left relationships that are predominantly caused by a constriction of the dental arches (unilateral or bilateral crossbite)
Vertical plane - used to give the superior-inferior relationships (deep bite or open bite)
Vertical
67
In a pt with class 3 skeletal malocclusion, which cephalometric measurement is increased?
SNB (sella-nasion-B point) (over 80degrees)
| SNB under 80 degrees is recursive mandible
68
What is the most ideal media to store an avulsed tooth that preserves the viability of the PDL?
Hank’s balanced salt solution
It has the ability to keep the cells surrounding the root viable
It has a rich amount of metabolites such as Ca, K, glucose, and phosphate ions that are sufficient to provide the cells with energy to sustain their normal cell metabolism until replantation can occur
HBSS also has a balanced pH and is known to hep replenish lost metabolites within the PDL cells of an avulsed tooth. It helps improve the prognosis of replantation and decreases the chances of having replacement resorption
69
What is the most likely outcome of an intruded permanent incisor in a 7 year old child in a few weeks after the trauma?
Re-eruption
An intruded permanent central incisor will eventually start to re-erupt within a period of approximately 2-3 weeks
The deicision on the mode of treatment for an intruded tooth may vary depending upon the severity of tooth intrusion and the maturity of its roots
70
Name 3 modalities of treatment for an intruded tooth.
Passive reposition which provides enough time for the re-eruption of intruded tooth
Active repositioning which is performed through surgical repositioning
Orthodontic repositioning which is achieved with the use of removal or fixed appliances
71
Trauma incurred to a developing tooth bud during the initiation and proliferation phase will likely result in an alteration in...
Number of teeth
Abnormalities in the number of teeth manifest from a disturbance during the initiation and proliferation stages of tooth development, hypodonti, oligodontia, anodontia, hyperdontia, and supernumerary teeth are various developmental disturbances that can affect the number of teeth present.
72
What is the difference of hypodontia and oligodontia?
Hypodontia - there are fewer than six congenitally missing teeth. It is also known as partial anodontia
Oligodontia - there are 6 or more congenitally missing teeth
73
When the ___ tooth erupts, it moves mesially and maintains a stable position within the corner of the mandibular arch
Permanent mandibular canine
74
When is a direct pulp cap Of a non carious exposure contraindicated?
When the pulp has been exposed for more than an hour
75
A patient presenting with teeth that appear to have bulbous crowns, an absence of a root canal system, and short roots radiographically likely has what condition?
Osteogenesis imperfecta
76
____ is the most common congenital bone disorder where patients are born with defective connective tissue, or without the ability to make it usually because of deficiency of type 1 collagen.
Osteogenesis imperfecta
77
____ is suggested radiographically by a thin bone cortex and bulbous crowns, obliterated pulps, and shortened tooth roots. The teeth are described as shell-like because the enamel may fracture and increased wear can occur.
Osteogenesis imperfecta
78
In osteogenesis imperfecta, Type 1 collagen is of normal ___ but is produced in insufficient ___. It results in ___ and ___.
Quality
Quantity
Blue sclera and easily fractured bones
79
In osteogenesis imperfecta, type 2 collagen is not of a sufficient ___. It results in what three things?
Quality or quantity
Most cases die within the first year of life due to respiratory failure or intracerebral hemorrhage
Patients have severe respiratory problems due to underdeveloped lungs
Patients have severe bone deformity and small stature
80
In primary teeth, what is the least reliable in assessing the pulp vitality?
Pulp testing
81
Name 5 prodromal symptoms of herpetic gingivostomatitis
Fever
Anorexia
Irritability
Malaise
Headache
82
At which stage of tooth development is tetracycline incorporated into the developing tooth?
Mineralization - because it forms a chelate with calcium
Tetracycline staining is found in both the enamel and dentin. When first incorporated into the tooth structure, tetracycline produces a yellow color that changes to brown and grey with the addition of sunlight over time.
83
Congenital syphilis is associated with ___ incisors occurring in months __-__ in utero before calcification begins.
Hutchinson’s
4-6
84
How are enamelomas (enamel pearls) formed?
During tooth development when the cells of the epithelial root sheath remains stuck to predentin. They then differentiate into ameloblasts and deposit enamel where it normally would not.
85
A child exhibiting signs and symptoms of failure to thrive, such as enamel hypoplasia, might also be suffering from which of the following conditions?
Ectodermal dysplasia
Ectodermal dysplasia may affect all types of tissues that originated form the ectodermal embryonic layer. Patients with ectodermal dysplasia may also suffer incomplete development of hair, nails, sweat glands, enamel of the teeth, and even the oil glands.
86
In a ____ mixed dentition analysis, the measurements of ___ will indicate the space that will be occupied by the unerupted canines and premolars.
Mandibular incisors
It uses the total MD width of the mandibular central and lateral incisors to predict the size of the unerupted canines and premolars.
87
What is the most likely age range for a primary herpetic gingivostomatitis episode?
1-5 years
88
Secondary herpetic gingivostomatitis is a deactivation of the latent virus due to ___, __, or ___. The vesicles may be found intraorally or exterorally on ___ surfaces.
Trauma, stress, immunosuppression
Keratinized
89
Following facial trauma, an 8-year old pt presents with a fractured central incisor that has an exposed pulp. Radiographic assessment shows the tooth still has an open apex. The pulp tissue appear to be vital and the tooth is non-mobile. What is the indicated treatment?
Pulpotomy with calcium hydroxide (cvek pulpotomy)
The root apex of developing permanent central incisor is still open. By performing a Cvek pulpotomy, the root of the central incisor will have extra time to complete its root development. (Pulpotomies are only performed as a temporary treatment option in permanent teeth while you wait for the roots of the tooth to fully develop so a root canal treatment can be performed)
90
A partial pulpotomy for traumatic exposures is also called ___
A cvek pulpotomy
91
What is the most common (75% of cases) type of leukemia in children?
ALL (acute lymphoblastic leukemia)
92
True or false... epinephrine in local anesthetics are contraindicated in patients with multiple sclerosis.
True, because it can aggravate the condition by regulating the activation of blood lymphocytes.
Elevating the levels of epinephrine also increases blood lymphocyte activity which could cause further damage to the myelin sheaths of the neurons thereby aggravating the multiple sclerosis condition
93
True or false... due to the long axis of the teeth, the spontaneous closure of extraction spaces in the mandibular arch is more successful than in the maxilla
False.. the upper arch is better than the lower arch
94
What is the greatest risk to a patient with adrenal insufficeincy if they are subjected to a highly stressful situation?
Cardiovascular collapse
Adrenal insufficiency occurs when the adrenal glands produce insufficient amounts of steroid hormones like cortisol and aldosterone.
95
Cortisol stimulates ___ in the liver.
Gluconeogenesis
It helps maintain normal blood pressure during stressful situations and creates additional energy to cope up with such stress
96
What are the signs and symptoms of Cushing’s syndrome?
Extreme weight gain
Buffalo hump (fat deposition in the upper central back)
Moodiness, irritability, or depression
Muscle and bone weakness
Memory and attention dysfunction
Osteoporosis
Diabetes mellitus
Hypertension, immune suppression, sleep disturbances
Menstrual disorders, hirsutism, baldness, hypercholestroemia edema
97
What are the 5 domains of pediatric patient management?
Aversive (punishments)
Linguistic
Pharmacological
Reward-oriented
Physical
98
Incidence of ____ is a condition in which cementum overlying the roots of at least two teeth connects to join the teeth together. It is more common in cases of trauma or crowding of teeth. This condition is most common in ____ teeth. How is it different from fusion?
Concrescence
Permanent molar
Different from fusion because it occurs following eruption and involves only cementum
99
True or false... crossbite can be corrected immediately during the primary dentition
True
100
What is methylphenidate?
A psychostimulant approved in treating people with ADHD.
101
Methylphenidate reduces the ___ and ___ reuptake, increasing their levels thereby improving their function as neurotransmitters in the brain. It elicits a similar pharmacological effect to cocaine. However this drug has a lower level of ___ and duration is [longer/shorter].
Dopamine and norepinephrine
Potency
Longer
102
Rheumatic fever is an inflammatory disease that occurs after a ___ infection or ___ and is caused by antibody cross-reactivity from the ___ protein.
Streptococcus pyogenes
Scarlet fever
Strep M
103
What are the Major criteria under the Jones classification of Rheumatic fever?
Polyarthritis
Cariditis
Subcutaneous nodules
Erythema marginatum
Chorea (St. Vitus’ dance)
104
____ is a condition comprised of generalized exocrine dysfunction, steatorrhea, and chronic pulmonary disease. It is a genetic disorder resulting in the inability of the body to transport salt and water in and out of cells. The result is excessive production of sticky and viscous mucus in the lungs and digestive tract. It affects the production of digestive enzymes that break down fats causing them to not be absorbed, resulting in a fatty stool called steatorrhea.
Cystic fibrosis
105
____ is fracture lines that do not extend into dentin.
Crazing
106
Name 5 potential causes of orofacial clefting.
Maternal nutrition - low intake of folic acid
Alcohol and cigarette use
Nitrate compounds and organic solvents
Lead
Medications
107
During the ___ in utero, when orofacial clefting may occur, the embryo is very sensitive to environmental pollutants and malnutrition
Sixth week
108
Piezoelectric currents are important for ___, not ____.
Bone maintenance
Orthodontic tooth movement
109
It takes ____s for fluid to be expressed from the PDL and the tooth moves in the socket
1-2s
110
What occurs after 3-5s of light force?
What occurs after 3-5s of heavy force?
Blood vessels distorted, no pain.
Blood vessels occluded. Pain is produced from crushing pressure.
111
What occurs after minutes of light force?
What occurs after minutes of heavy force?
Blood flow and oxygen levels altered. Increased prostaglandin and RANKL
Blood flow is cut off
112
_____ resorption occurs with light force after ~___days. It involves both osteoclasts and osteoblasts
True
2
113
____ resorption begins after ~___ days of heavy force, it ends after ____ days
Undermining
3-5
7-14
114
In light force... the first wave of osteoclasts/osteoblasts come from ___. Later, the second wave comes from ___.
The PDL
The blood supply
115
What occurs after hours of application of a heavy force?
Sterile necrosis (no bacteria involved)
Hyalinized PDL (no cells)
116
How long does it take after sterile necrosis and after tooth movement via undermining resorption to heal before the next adjustment?
~2 weeks
117
Remodeling of gingival fibers takes about ___, which is why you want to wear your retainer as much as possible after orthodontic treatment.
1 year
118
In controlled tipping, where is the center of rotation?
At the apex of the root
119
In bodily movement, where is the center of rotation?
Infinitely past the apex
120
When torquing, where is the center of rotation moved?
Coronally
121
What is the optimal force for bodily movement of teeth?
100g
122
What is the absolute minimum for tooth movement to occur?
4-8 hours
The longer you have an appliance working the better
123
Patient-activated removable display a ___ type of force decay
Intermittent
124
What type of force decay do we want for light forces? What about heavy?
Light = continuous
Heavy = interrupted
125
Define stress and strain
Stress = internal force
Strain = internal displacement
126
Stress is measured in ___
Strain is measured in ___
Mega pascals
Mm
127
What is the difference between elastic deformation and plastic deformation?
Elastic deformation = goes back to its original shape
Plastic deformation = doesn’t return to its original shape. It undergoes a permanent change
128
When stress/strain have a linear relationship, the slope is called the ___. The steeper the slope the more [elastic/stiff] that material is.
Elastic modulus (modulus of elasticity)
Stiff
129
What is the proportional limit?
What is the yield point (yield strength)?
proportional limit = The highest point on the stress/strain curve that is still linear. Once you get past this, it isn’t completely elastic
Yield point = initial point where plastic deformation begins
130
What is ultimate tensile strength?
Maximum load an object can withstand
131
What is the area under the stress-strain curve of the elastic portion? What does it mean?
Resilience = energy storage capacity of the object as you are stretching it
132
What is the area under the stress/strain curve of the plastic deformation curve? What does it mean?
Formability = the ability to undergo plastic deformation without breaking
133
If you double the diameter of a wire, you increase strength __X. Increase stiffness ___X. And decrease range by ___.
8x
16x
1/2
134
If you double the lengthening of a wire you ___ the strength, but make it ___X springer and ___x more range
Half
8x
4x
135
A wire that is attached to two teeth by two brackets is considered a ___ beam. If it is loosely attached it increases strength by __x. If it is tightly fixed the strength increases by ___.
Supporting
2x
4x
136
Rubber bands have a great ___ range. They ___ easily. And they provide ___ forces rather than __.
Elastic
Fatigue
Interrupted rather than continuous
137
What is a pseudo class 3 malocclusion?
They start out as end-end in CR but then protrude to a functional occlusion in MI with their mandibular incisors anterior to maxillary incisors
If not treated it can lead to tooth wear and/or perio problems
138
What is the treatment for a dental anterior crossbite?
Tip maxillary incisors labially
Add a bulk of acrylic to the removable appliance (Hawley retainer) to separate the arches and prevent occlusal interference during tooth movement
139
A fingerspring works effectively for ___-___ mm of activation. It affords to ___mm of tooth movement/month
2-3mm
1mm
140
Where should the helix be placed in a finger spring?
Opposite to direction of intended tooth movement (usually MD)
141
What is a Z-spring?
Double cantilever
Second beam with a second helix.
2mm of activation per helix.
142
A Z-spring usually allows for __ movement
FL
143
What is a whip spring?
Attached to a fixed lingual arch and functions to tip incisors labially
Allows for 1mm/month
144
What is the best option for retention following correction of a crossbite?
Hawley retainer
145
How do you treat a skeletal class 3 malocclusion due to maxillary deficiency with growth modification?
Reverse pull headgear
146
At what age should reverse pull headgear be used?
Age 7 or 8, before skull fissures fuse
147
How can you treat a skeletal class 3 malocclusion using fixed appliances?
Class 3 elastics
Age 11, TADs with mature bone
148
What is the “rule of thumb”
Put your thumb at the top of the palate, if it fits, the posterior crossbite is likely due to lingual tipping
If the thumb doesn’t fit it means the crossbite is likely due to a narrow palate (narrow palatal vault)
149
What can thumb-sucking habit cause?
Maxillary constriction from buccinator
Unilateral posterior crossbite due to functional shift
Tooth wear, dental compensation, crowding
150
How do you treat posterior dental crossbite (palatal tipping of maxillary teeth)?
Expansion of lingual arches (slow expansion) for primary and early mixed
151
A W-arch for expansion is usually made with a ___ wire. It is used at age __-__. You can expect to get ___mm/month.
.036” SS
8-11 (when midpalatal suture is open)
2mm
Some suture opening may occur
152
A quad helix appliance is made with ___wire. It has 4 helices so it has a better range of action. Treatment is usually __-__ months. It should be worn for ___ months for retention.
.038” SS
2-3 months
3
153
When would cross-elastics be used?
It may cause ___ as a side effect.
The amount of force is ___
For unilateral or individual teeth in crossbite
Use a mandibular lingual arch to stabilize lowers
It may cause some extrusion
150-170g
